The New Holland T6.155 tractor (155 hp) features a digital instrument cluster with warning lights for engine, transmission, hydraulics, and emissions systems. Understanding these indicators helps prevent downtime and costly repairs in the field.
New Holland T6.155 Warning Light Symbols
| Symbol | Name | Color | What it means | What to do |
|---|---|---|---|---|
| Check Engine | AMBER | On the T6.155, this light signals an engine fault detected by the ECU, often related to emissions or sensor readings. | Reduce load and check for diagnostic codes using the instrument panel or service tool. | |
| Engine Oil Pressure | RED | Indicates low engine oil pressure, which can cause severe damage if ignored on your T6.155. | Stop engine immediately and check oil level; if full, contact dealer. | |
| Battery / Charging | RED | Shows the battery is not charging or voltage is low, typical if alternator belt slips or battery fails on T6.155. | Check alternator belt tension and battery connections; recharge or replace battery. | |
| Coolant Temperature | RED | Engine coolant temperature is too high, often due to blocked radiator or low coolant on T6.155. | Stop engine, let cool, then check coolant level and radiator fins. | |
| Transmission Temp | AMBER | Transmission oil temperature is elevated, may occur during heavy PTO work or high ambient heat on T6.155. | Reduce load or shift to a lower range; allow transmission to cool. | |
| Brake System | RED | Indicates a brake system fault, such as low brake fluid or excessive wear on T6.155 disc brakes. | Check brake fluid reservoir and inspect pads; do not operate until fixed. | |
| Parking Brake | GREEN | Parking brake is engaged; disengage before moving the T6.155. | Release parking brake lever before driving. | |
| Glow Plug / Preheat | AMBER | Glow plugs are preheating the engine for cold starts; wait until light turns off on T6.155. | Wait for light to extinguish before cranking the engine. | |
| DPF / Regeneration | AMBER | Diesel particulate filter is regenerating or needs a parked regen on T6.155; may flash for high soot level. | If flashing, perform parked regeneration following instrument panel prompts. | |
| DEF / AdBlue | AMBER | DEF level is low or quality issue; T6.155 will limit power if ignored. | Refill DEF tank with certified fluid; if light persists, check system. | |
| Water in Fuel | AMBER | Water detected in fuel filter/water separator; drain immediately to prevent injector damage on T6.155. | Drain water from the separator bowl located on the fuel filter housing. | |
| Low Fuel | AMBER | Fuel level is low; refuel soon to avoid air ingress on T6.155's common rail system. | Add diesel fuel; avoid running dry. | |
| High Beam | BLUE | High beam headlights are on; switch to low beam when approaching other vehicles on T6.155. | Pull the turn signal lever to toggle high beam off. | |
| Hydraulic System | RED | Hydraulic system fault, such as low oil level or filter blockage on T6.155’s open-center system. | Check hydraulic oil level and filter; if OK, contact dealer. | |
| Fasten Seat Belt | RED | Seat belt not fastened; mandatory for T6.155 operation with cab. | Fasten your seat belt before moving the tractor. | |
| Reduced Power (Limp Mode) | AMBER | Engine power is reduced to protect components, often due to DEF or emission fault on T6.155. | Diagnose fault codes; contact dealer if unable to clear. | |
| Engine Oil Temperature | AMBER | Engine oil temperature is high; may occur during prolonged heavy PTO work on T6.155. | Reduce engine load or stop and let idle to cool. | |
| Air Filter | AMBER | Air filter restriction detected; clean or replace to prevent power loss on T6.155. | Inspect and replace air filter element if dirty. | |
| Fuel Filter / Water Separator | AMBER | Fuel filter needs service or water in separator; T6.155 requires regular maintenance. | Replace fuel filter and drain water separator; prime system. | |
| Service / Hour Meter | AMBER | Scheduled maintenance due based on engine hours on T6.155; service as per manual. | Perform oil change, filter replacement, and inspections per schedule. | |
| Work Lights | GREEN | Work lights are on for nighttime field operations on T6.155. | Turn off when not needed to save battery. | |
| Beacon / Rotating Light | GREEN | Beacon light is activated for road visibility on T6.155. | Use on public roads as required by law. | |
| Differential Lock | GREEN | Rear differential is locked for traction in slippery conditions on T6.155. | Disengage when turning on hard surfaces. | |
| PTO Engaged | GREEN | Power take-off is engaged; disengage before stopping engine on T6.155. | Turn off PTO when not in use. |
24 symbols shown. Icons follow ISO 2575 dashboard standards; exact graphics vary by model year.
Most Important Warning Lights
Engine Overheat
Common causes
- Blocked radiator fins
- Low coolant level
- Faulty thermostat
What to do
On T6.155, stop engine immediately, check coolant reservoir and radiator core. Clean debris from radiator and add coolant if low. If persists, inspect thermostat.
Transmission Overheating
Common causes
- Excessive load in high range
- Low transmission oil level
- Clogged cooler
What to do
Reduce load or shift to lower range; let transmission idle to cool. Check oil level and add if needed. Clean cooler fins with compressed air.
DEF System Failure
Common causes
- Empty DEF tank
- Poor quality DEF fluid
- Faulty NOx sensor or injector
What to do
Refill with certified DEF; if light stays, dealer diagnosis may be needed. Do not bypass system; T6.155 will reduce power.
Low Oil Pressure
Common causes
- Low oil level
- Oil filter clogged
- Oil pump failure
What to do
Stop engine immediately. Check oil dipstick; add oil if low. Replace oil filter. If pressure remains low, internal engine damage may have occurred – contact dealer.
Hydraulic System Fault
Common causes
- Low hydraulic oil level
- Clogged suction filter
- Relief valve stuck
What to do
Check hydraulic reservoir and add oil. Replace hydraulic filter. If still faulty, consult dealer for valve adjustment.
Frequently Asked Questions
What does the flashing DPF light mean on my T6.155?
A flashing DPF light indicates high soot load; you must perform a stationary regeneration. Park in a safe area, apply parking brake, and follow the instrument menu prompts to initiate regen.
Why does my T6.155 show 'Check Engine' after refueling?
If the light comes on after refueling, it may be due to a loose fuel cap or air in the system. Tighten the cap and clear the code using the instrument panel or key cycle. If persistent, check for fuel leaks.
How often should I change the transmission oil on the T6.155?
Transmission oil should be changed every 600 hours or annually, whichever comes first, per the maintenance schedule. Use only New Holland approved oils.
The amber warning light with a wrench icon is on—what is it?
That is the service reminder (hour meter). It indicates scheduled maintenance is due. Check the operator manual for required service at the current hour count.
Can I drive with the 'Reduced Power' light on?
Yes, but tractor power is limited to protect the engine. You can operate at reduced speed to return to the barn or dealer. Avoid heavy PTO work until the fault is corrected.
What does the 'Water in Fuel' light mean?
It means water has collected in the fuel filter/water separator. Drain it immediately by opening the drain valve at the bottom of the filter bowl. If the light remains, replace the filter element.